the keys to reproducing are that (1) you need to keep the Filters menu open (don’t click Update) when (2) you click on Your Observations. (here, you’re not clicking the Your Observations check box in the Filters menu. you’re clicking the Your Observations link the the main menu, which will take you to an Explore page that’s preset with just your observations.)
Yes, sorry that I didn’t specify it, I didn’t think about button in filters, interesting that it doesn’t work that way if I choose the end date, only first one.